A remote-sensing satellite of earth revolves in a circular orbit at a height of 0.25 × 10⁶ m above the surface of earth. If earth's radius is 6.38 × 10⁶ m and g = 9.8 ms^–2, then the orbital speed of the satellite is

7.76 km/s

v = \(\sqrt{\frac{GM}{r}}\)

v = \(\sqrt{\frac{GM}{R + h}}\)

g = \(\frac{GM}{R^2}\)

GM = gR²

v = \(\sqrt{\frac{gR^2}{R + h}}\)

v = R\(\frac{g}{R+h}\)

g = 9.8 m/s² ; R = 6.38 x 10⁶ m ; h = 0.25 x 10⁶ m

V_o = 7.76 km/s